


One Good Turn

by ShippersList



Series: Trope Train [22]
Category: Marvel Cinematic Universe
Genre: Alpha/Beta/Omega Dynamics, Alpha/Omega, Alternate Universe - Canon Divergence, M/M, Mating Cycles/In Heat, Mission Fic, Non-Traditional Alpha/Beta/Omega Dynamics, Pseudo-Science, References to Knotting, Slight gender dysphoria, Trope: gender swap
Language: English
Status: Completed
Published: 2016-12-29
Updated: 2016-12-29
Packaged: 2018-09-11 09:34:40
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,493
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8974393
Author URL: https://archiveofourown.org/users/ShippersList/pseuds/ShippersList
Summary: What to get the spy/assassin who has everything? When Clint and Natasha stumble upon a strange device during an op, an unthinkable happens. As a result, Clint, Natasha, and Phil all get what they want.





	

**Author's Note:**

  * For [chocobith](https://archiveofourown.org/users/chocobith/gifts).



> My giftee asked for pining, get together, ABO, fluff, and smut (amongst other things, but these I managed to include). I hope you like the slight twist in the story. 
> 
> Title from the proverb _Quid pro quo_ that translates as _One good turn deserves another_.
> 
> Hugs and thanks to [lola](http://archiveofourown.org/users/lola381pce/) for the beta work—again!

They were six hours into the mission when the communications with Strike Team Delta went down.

Phil Coulson swore under his breath.

Contrary to popular belief, he wasn’t always calm during an op. He knew he sounded like that but that was simply because he’d honed the skill of projecting calm competence to an art form.

Going on a mission right before Christmas was never ideal, but since the bad guys didn’t have nine-to-five working hours, Phil had agreed on it anyway. None of his team had anything better to do; they’d already decided to spend the Christmas Eve together (as per Clint’s wishes) but they’d agreed on not buying each other anything. Besides, what could you even get a spy or an assassin who had everything already?

He tapped his comm link even though he knew it was futile. Phil had always disliked being cut off from his team, even when it was planned and he would stare at the clock and count seconds to the moment when the radio silence ended. It wasn’t like he didn’t trust his team because he did. It wasn’t even about him being an alpha. It was just his nature to look after his people. So, landing on a mission where he lost both communications with Strike Team Delta _and_ was forced to retreat into the secondary base while in the dark made him cranky enough for Johnston, the backup team’s beta handler, to give him a wide berth.

Seventeen agonizing minutes later, when the communications finally came back online, the first thing Phil heard was static.

The second was Natasha.

_”—damnit! Phil come in. We need an extraction, now. No, no, Clint, stay with me…”_

Phil’s heart lurched at the string of colorful Russian swearing and the odd ring in her voice.

”Widow, what is it?” he barked. Behind him, Johnston perked up.

 _”Finally! Everything’s clear. Get in here. I can’t—”_ She stopped to let out a frustrated growl. _”I can’t get him out. He needs you.”_

Phil was already moving. He threw a glance at his backup team and got a grim nod from Johnston. They all knew that if shit went down, he went after his team. Phil Coulson never left anyone behind.

But this time, it wasn’t just anyone. It was Clint.

 

* * *

 

Natasha was waiting for him near the entrance to the warehouse. At first glance, she seemed fine but when Phil got close enough, he stopped as if he’d collided with a brick wall. Instead of her familiar, subtle omega presence, he faced an alpha. Nearly out of control, freshly presented alpha.

He swayed and shook his head. ”What—?” he ground out. His own alpha side rippled just under his skin and he gripped it tight, forcing it to stay down.

Natasha blinked several times before she slowly averted her eyes and tipped her head to the side to bare her neck in submission. The gesture warred with her all-over-the-place scent, but Phil was a mature alpha and trusted the visual signs of her recognizing his rank.

Nevertheless, it took him a moment to get himself to relax. Usually, he had an iron control of his secondary gender, but Natasha had taken him by surprise. With deliberate effort, he unclenched his jaw and asked, ”Where is he?”

Keeping her neck exposed, Natasha answered in a growl, ”He’s in there. But you should be careful.”

Instinct made Phil bare his teeth at her tone before he got a grip of himself. He took a couple of deep breaths to steady himself lest he barged in on Clint in full protective alpha/handler mode. It did little to ease his mind, though, because instead of clear air, he filled his lungs with Natasha’s new, jarring alpha pheromones.

Mixed with her scent he spied an undertone of something else, sweet and familiar in its unfamiliarity. He couldn’t help leaning into the scent and taking a step forward before he caught himself.

It took him embarrassingly long to understand: If Natasha was an alpha now, it could only mean that Clint was an omega.

”You changed genders,” he said quietly. ”How the hell did you manage in that?”

Natasha pressed her lips together in a tight line. ”This place was one of The Wizard’s,” she said slowly after a moment. ”We found a… device.”

The rest was left unsaid, but Phil understood it well enough.

Secondary genders weren’t a thing SHIELD put much emphasis on. The agency offered military grade suppressants to both alphas and omegas and discreetly kept tabs on when the individual omega agents were due to their mandatory, annual heat leave. Apart from that, nobody cared. In SHIELD, the results mattered more than the symbol on your ID.

Phil had learned enough of Natasha’s past to know that Red Room had abused and brainwashed her during prolonged, induced heat cycles. After SHIELD had taken her in, she’d butt heads with Phil several times and tested his boundaries and his character. She’d even tried to seduce him when she was in heat. Phil had let her down gently but firmly and eventually, she had grown to respect him.

After that one try, Natasha never attempted to use her omega side on Phil again, for which he was grateful. He wasn’t blind or scent-deaf, and he most certainly wasn’t above having a good time with an attractive omega, but he preferred his partners willing and fully consenting.

After years of abuse, Natasha had fought the majority of her life to overcome her conditioning. She wouldn’t overlook a chance to completely change her designation.

What Phil didn’t quite understand was why Clint had gone along with it.

”It was his idea,” Natasha said quietly, as if she had read his mind.

”But… _why?”_

”That’s something you need to ask him,” she answered. Without a further comment, she stepped aside and motioned Phil to go in.

The room in front of him was cavernous, lit with odd, shady lights that made it look like something straight out of a sci-fi novel. When Phil cautiously stepped forward, he saw the mangled remains of what had been The Wizard’s device Natasha had told him about. Behind it, huddled by the wall, was Clint.

Before he even smelled him, Phil could see Clint was afraid and overwhelmed. Despite his reputation as an unruly and reckless mercenary, Clint had never been that interested in power plays to start with—a gift from his late father, Phil knew—and he’d fallen quite easily under Phil’s command soon after he had learned to trust him. It had been years since Phil had last seen Clint curled up in himself like that. It broke his heart.

”Clint?” he called out in a calm, soothing tone.

Clint shuddered and let out a ragged breath.

”Are you injured?” Phil paused for a moment, then continued with a sliver of alpha in his tone, ”Barton, report.”

He realized his mistake immediately when Clint whimpered.

_Shit!_

He should’ve known better than use his alpha voice. Clint was presenting, sliding into heat, and any show of alpha dominance would most likely just speed the process up.

After a short moment of frantic thinking, Phil decided to revert to formal procedures when dealing with compromised Agents. Keeping his tone carefully neutral, he asked, ”Agent, do I have permission to approach?”

”Yeah,” Clint managed.

Phil nodded to himself and walked slowly to kneel by Clint’s side. Up close, his scent was even more appealing, sweeter and fresh, and Phil barely managed to catch himself in time before he dove in for a deeper lungful. Detecting someone’s scent in social interactions was one thing, uninvited deep scenting was just rude, no matter how good their working relations were.

Or how attractive Phil had always found Clint, secondary designations aside.

He swallowed around a dry throat and pressed the nail of his left forefinger on the nail bed of his thumb to ground himself with the sharp flash of pain. ”Can you get up?” he asked, carefully keeping his hands on his lap.

”Dunno,” Clint said and chuckled weakly. ”Shit, this feels nothing like I’d imagined.”

Phil frowned. ”Is this something you’ve thought about?” he asked, bemused.

Clint made an awkward shrugging motion with one shoulder. ”Sometimes, yeah,” he mumbled and pushed himself to sit properly up, ducking his head to hide his face.

His answer caught Phil by surprise. He’d been Clint’s direct supervisor and sometimes confidant for almost a decade, and he hadn’t had a clue. True, Clint had never really enforced his alpha status, but neither had he hinted about feelings of gender dysphoria.

But it was neither here nor there. At the moment, the most important thing was to get his team out safely, so Phil drew on his professional Agent Coulson persona and set on the task of emergency extraction.

He could deal with Clint’s revelation later.

 

* * *

 

Fury’s face was quite a sight when Phil gave him his personal off-the-record report.

”They fucking did _what?”_

”Swapped designations,” Phil repeated with a calm he didn’t actually feel. ”And they destroyed the device right after. The Wizard wasn’t found on the compound and no-one has any idea of his whereabouts, so even if they were inclined to swap back, it would be hard to achieve.”

Fury narrowed his eye. ”What do you mean, ’If they were inclined?’” he asked slowly.

Phil paused for a moment to think about how to phrase the statement. ”The swap was done in mutual understanding. There was no coercion, and if you asked them, neither Agent Romanoff nor Agent Barton would be willing to attempt a re-swap.”

Fury swore long and hard under his breath. Phil raised a brow at the language — there were several he hadn’t heard before. He should try to remember them for later use.

Finally, Fury shot him a glare and asked, ”Well, what are you going to do about it?”

Phil blinked. ”Me?”

”Yes, you,” Fury huffed. ”They’re your strike team. You need to figure this out. I have no time for this shit.”

”Okay,” Phil said because he didn’t know what else to say.

”Good. Now get the fuck out of my office,” Fury grumbled.

Slightly dazed, Phil walked out and gave an absent-minded smile at Fury’s secretary chiming ”Merry Christmas!” in his wake.

 

* * *

 

Dr. Sandero spotted him the moment he walked in. ”Agent Romanoff already signed off,” she said and beckoned him into her office. ”All her tests came back normal for a newly presented alpha female.”

Phil nodded. He wasn’t even remotely surprised: Natasha wanted to acclimatize on her own terms. She would emerge when she once more felt secure in her own skin.

”Agent Barton, on the other hand…”

”What about him?” Phil asked, slightly sharper than was probably necessary.

Unfazed, Dr. Sandero closed the door behind her. ”As you are well aware, he’s presenting as an omega. So far, everything seems to be going alright, but—”

”—But what?”

”I’m going to be blunt,” Dr. Sandero said. ”Due to his primary gender, Agent Barton is going through a bigger change than Agent Romanoff. His body has transformed into the one of a regular male omega, and managing the change will affect him on both physical and emotional level.” She shook her head. ”If he was originally an omega and this was a drug-induced heat, we could suppress it. But he’s presenting and it would be extremely risky to interfere now.”

Phil nodded. During puberty, newly presented teenage alphas and omegas always went through their first ruts and heats to let their bodies acclimatize to the new hormone levels, unless there was a serious medical reason not to. In those cases, their alpha/omega traits were medically suppressed from the beginning, and they lived their lives basically as betas.

Presenting was a hormonal storm and having a counterpart to balance the hormones out helped. The younger the teen, the more often the counterpart was a parent who helped the teen to balance their hormones with cuddles. The older teens usually opted for sexual release, either with a boy- or a girlfriend or a selection of toys.

Clint was closer to forty than thirty, and Phil didn’t even want to think about what havoc his hormones were wracking on his body.

”So, he needs someone to help him through it,” he concluded slowly.

”Yes,” Dr. Sandero said. ”And he asked for you.”

The alpha in him vibrated with pride at being chosen, but Phil suppressed it with ruthless efficiency and asked, ”Is he even capable of making such a decision right now?”

”I think we both know just how far Agent Barton is capable of pushing himself when it comes to medical issues,” Dr. Sandero said dryly. ”And yes, he gave his informed consent in front of witnesses.” She gave Phil a considering look. ”The question is, are you up to it? I know I don’t have to remind you about the significance of heat bonding and how much it can affect work relations.”

Phil shook his head. ”Don’t worry about me. This is about him.”

As he determinedly walked towards the heat suite Clint was in, he missed Dr. Sandero’s knowing look.

 

* * *

 

No matter how confident Phil had been, he was forced to reassess his position when he opened the door. Clint was in almost full heat already, and his ripened scent called for Phil who let out a low growl before he even realized what he’d done.

Mortified, Phil closed the door behind him and leaned on it, taking in the room.

The heat suite was surprisingly cozy, furnished with a giant bed, a dresser stacked with soft towels and bath robes, a well-stocked fridge, and a spacious bathroom complete with a bathtub that could fit two full-grown men. Despite the suite being a medical room, there were no windows or cameras and the nursing staff could only listen in when the speaker was pressed from the inside. Several alarm buttons were subtly hidden around the room and a Stark-provided program kept a remote eye on vital signs in case of an emergency.

Clint was sitting at the edge of the bed, his hands clenched in fists on his thighs. There was a sheen of sweat on his brow and his breathing was shallow. Too shallow, Phil noted.

”Do you know why I am here?” he asked. His voice was rough and low, a result from Clint’s heat pheromones.

Clint nodded.

Phil swallowed. ”Words, Clint. I need to hear your words.”

Clint’s tongue darted out to lick his lips. ”I made the decision to swap mine and Nat’s genders. I’m presenting as an omega.” He closed his eyes. ”I asked for you to help me through this, but. I— I don’t want you to be here just because you feel obligated.”

”I’m not,” Phil answered hoarsely.

Clint’s eyes flew open and his stare bore into Phil, intense and vulnerable at the same time. ”In that case… Would you, Phil Coulson, do me the honor of helping me through my heat?”

The formal words were how alphas usually asked omegas’ permission. Phil blinked answered, softly, ”The honor is all mine.”

Clint let out a needy sound and tipped his head back, offering Phil his throat. It was all Phil needed to hurry across the room and lean down to inhale Clint’s scent, to get drunk on it. He let go and indulged his alpha side by sucking at the soft skin under Clint’s ear, feeling unreasonably proud at the blossoming purple mark he left behind.

”Phil… please…” Clint said, reaching out for him.

”Anything,” Phil answered. ”Just tell me what you want.”

He stripped himself and tossed his clothes into the corner. When he turned around, Clint was staring at him with his mouth slightly open and eyes wide with lust. If it was any other situation, Phil would’ve rolled his eyes at himself preening under the attention, but now it only made him proud.

Clint, _gorgeous Clint_ felt that Phil was worthy of him.

”May I?” he asked.

Clint nodded and Phil proceeded to undress him slowly, kissing every strip of skin he revealed. He helped Clint lay down in the middle of the bed in all his naked glory and it didn’t take long for Clint to be pliant and blissed out under his hands. They whispered _I’ve wanted this for so long,_ and _I never thought I could have this,_ and _Best Christmas present ever_ into each others skin, and when Phil finally sunk into him, they were both lost in the heady cloud of their combined scents.

It took Phil an embarrassingly short time to come, but Clint didn’t seem to mind. He cried out when Phil’s knot tied them together and arched beautifully as he came, trembling all over and clenching almost painfully around Phil’s knot.

Feeling thoroughly drained, Phil had barely the presence of mind to draw the blanket over them before he passed out, holding Clint in his arms.

 

* * *

 

Phil came back to with his nose buried in Clint’s neck and his arms wound around him, without a clue of how much time had passed.

”So,” Clint said.

Phil nuzzled the skin behind his ear, careful not to dislodge Clint’s hearing aid. ”Why didn’t you tell me before?”

Clint shrugged with his other shoulder. ”I dunno. I guess I was afraid that you’d think I’m a freak when I was still an alpha.”

”We’re SHIELD. Freak is what we call an average Tuesday,” Phil said calmly. ”And I wouldn’t have.”

”Really?” Clint asked, dubious. ”And you would’ve been okay with a—a male alpha team member who wanted to be a bitch?”

The harsh tang of his words and the sour note in his scent told Phil that Clint quoted someone, probably something that had been said to him too many times. Phil was having none of it. Gently, he tested if they could move and when he slipped free of Clint without too much trouble, he turned Clint around.

”Sexuality and gender identity are something a lot more intricate than a simple who takes what and into which hole,” he said, giving Clint a serious look. ”It doesn’t make a male alpha a bitch if he enjoys being fucked.”

”Yeah, right,” Clint snorted.

Phil kissed his nose. ”You’re free to fuck me later if you want to.” Then he paused, suddenly awkward. ”That is, of course, completely up to you,” he said, stammering a bit. ”I wouldn’t presume anything just because we share a heat bond.” He gave himself a mental slap for making plans further without any idea of what Clint thought.

Clint gave him a flat look. ”If you think I’ll ever want anyone else but you, you’re more stupid than I would’ve ever believed,” Clint retorted. ”I know that heat and rut declarations shouldn’t be taken for granted, but I’ve wanted you for years. If you want to know how long exactly, ask Nat.”

”How about not,” Phil said. ”But there is something I need to ask you,” he said after a moment. ”Why did you do it, anyway?”

Clint shrugged and developed a sudden interest in Phil’s chest hair. Phil let him and tried not to be distracted by the way Clint’s fingers danced on his skin.

”Did you know that when Nat was a kid, she wished Santa to make her an alpha?”

Phil shook his head. ”I didn’t know but I can imagine.”

Clint nodded. ”Yeah. And it’s not like being an alpha was big deal to me, you know?” He paused and let out a long breath. ”Besides, I thought I might have a chance with you if I was an omega. So I thought why not? Merry Christmas for everyone? Yay.” His words were light but he still didn’t meet Phil’s eyes.

”Your gender never mattered to me,” Phil said carefully. ”I was more worried of the power imbalance and of my being your handler, which was the reason I never said anything.”

Clint raised his head and frowned. ”You’re serious.”

”It’s a widely know fact that I don’t have a sense of humor,” Phil deadpanned.

Clint stared at him for a moment, blinked, and groaned, ”Fuck you.”

”Maybe later, if you’re amenable,” Phil agreed with a mild smile. ”But yes, I was—am— serious.” With his fingers, he gently tilted Clint’s chin up. ”Clint Barton, whether you’re alpha, omega, or something completely different, I’d be honored to be your alpha.”

Slowly, giving Clint time to stop him if he wanted, Phil leaned closer to give him a kiss. It was chaste, just a peck on the lips, but it felt more intimate than the heated, ravenous kisses they’d shared earlier. When he drew back, Clint’s eyes were closed and he was wearing a small smile.

Resting his head on the pillow, Phil closed his eyes and thought back at what Clint had moaned earlier.

He agreed: best Christmas ever.

**Author's Note:**

> If I've missed any tags you think are relevant, please let me know and I'll add them.


End file.
